This research program focuses on three health problems of concern to the Navajo Nation. One project is studying the extent of alcohol use and abuse and associated socio-economic and psychological factors among the Shiprock Navajo. A second project is attempting to establish the etiology of diarrhea among children through culturing stool swabs for Salmonella and Shigella. Specimens are sent to NIH for rotavirus studies, E. coli organisms are saved for toxigenic studies, and plans are to culture for Campylobacter faecalis and Yersina entercolitica. Ten sheep flocks are also monitored for diarrhea, and coincidental occurrences of diarrhea in the human and sheep populations are recorded. A third project is isolating beta-hemolytic streptococci from clinical sources, identifying through presumptive grouping of A, B, and D strains followed by verification of group A by the fluorescent antibody technique. Streptococcus viridans (alpha hemolytic) and Staphylococcus sp. are also identified to determine their coprevalence in strep infections. Data on individuals and households are computerized to identify recurrent sources of infection, household linkages and resistant reservoirs of infection, and the sharing of streptococcal flora by domestic animals and people.